We propose a semi-cooperative game theoretic approach to check whether a given coalition is stable in a Bayesian game with independent private values. The ex ante expected utilities of coalitions, at an incentive compatible (noncooperative) coalitional equilibrium, describe a (cooperative)...

The theoretical literature on collusion in auctions suggests that the first-price mechanism can deter the formation of bidding rings. In equilibrium, collusive negotiations are either successful or are avoided altogether, hence such analysis neglects the effects of failed collusion attempts. In...

This paper studies collusion in one-shot auctions, where a buyer can bribe his competitors into lowering their bids. We modify the single-unit Vickrey auction to incite deviations from the designated-winner scenario and thus undermine collusion. The construction of mechanism does not require the...

This study explores stability in efficient collusion in government procurement auctions. In first- and second-price auctions with independent private values, we look at the possibility of vetoing collusion mechanisms and the learning of the other bidders after vetoing. The collusions in...

The theoretical literature on collusion in auctions suggests that the first-price mechanism can deter the formation of bidding rings. In equilibrium, collusive negotiations are either successful or are avoided altogether, hence such analysis neglects the effects of failed collusion attempts. In...

We consider two ascending auctions and show that many of the (unwanted) collusive or signaling equilibria studied in the literature in the framework of the SEAMO (simultaneous English auction for multiple objects) don't have a counterpart in the JAMO (Japanese auction for multiple objects). We...

We propose an equilibrium theory of data-driven antitrust oversight in which regulators launch investigations on the basis of suspicious bidding patterns and cartels can adapt to the statistical screens used by regulators. We emphasize the use of asymptotically safe tests, i.e. tests that are...

We study the implications of delegating bids to a bidding agency for the revenues and efficiency of the Generalized Second-Price auction, the standard sales mechanism for allocating online ad space. The agency maximizes both its own profits and the advertisers' surplus and implements collusive...

This paper proposes a procedure to detect collusion in asymmetric first-price procurement. The main objective is twofold. First, to provide a methodology to detect collusion using a structural approach, and second to apply the methodology to field data on procurement auctions for highway...

We study optimal bidder collusion at first-price auctions when the collusive mechanism only relies on signals about bidders' valuations. We build on Fang and Morris (2006) when two bidders have low or high private valuation of a single object and additionally each receives a private noisy signal...